Light weightlifting, daily gardening or assisting with heart surgery several times a week: The stories demographer and researcher Dan Buettner has to tell stand out. The people engaged in these activities are all just under or already over 100 years old. They live in the so-called "Blue Zones".
These are five regions in which a disproportionate number of people live to be 100 years old or even older: Okinawa (Japan), Sardinia (Italy), Ikaria (Greece), Nicoya Peninsula (Costa Rica) and Loma Linda (California, USA). In Okinawa, there are 68 centenarians per 100,000 inhabitants. By comparison, Switzerland has about 22 centenarians per 100,000 inhabitants.
Longevity is explained less by genetic factors than by a combination of lifestyle and environmental factors. One important point is nutrition. To identify commonalities, Dan Buettner examined more than 150 dietary studies conducted in the regions over the past century.
So how do they eat, the centenarians from the "Blue Zones"? Probably the most striking characteristic is their 95 percent plant-based diet.
Small amounts of meat are consumed about five times a month, just under 60 grams or less per serving. Among these, chicken, pork and goat meat are eaten the most. It is also noticeable that the meat in the "Blue Zones" comes from free-range animals. They are not treated with hormones, pesticides or antibiotics and do not grow up in overcrowded fattening farms.
People in Loma Linda avoid meat entirely, but fish is readily consumed there. The Adventist Health Study 2 followed 96,000 Americans over an extended period of time. The results show that it was not vegans or meat eaters who lived the longest, but pescatarians. That is, people who ate a plant-based diet and ate a small portion of fish up to once a day.
In other "Blue Zones," fish was a common part of daily meals and was eaten on average two to three times a week. However, other health and ethical factors should also be considered when eating fish.
Sheep and goat milk products are used several times a week, especially in the traditional cuisine of Sardinia and Ikaria. In most cases, the milk is not consumed directly, but in the form of naturally fermented yogurt without added sugar.
Eggs also appear on the table in the "Blue Zones" as a side dish two to four times a week.
Goji berries, acerola cherries or camu camu: The "Blue Zones" do not rely on superfoods that are hard to pronounce and usually quite costly. They put a versatile and significantly less expensive food on the table every day: beans.
They are the cornerstone of every Blue Zones diet worldwide. Long-lived populations in these "Blue Zones" eat at least four times as many beans as the average American. As a WHO-funded study shows, 20 grams of beans per day reduces the risk of death by eight percent.
In the "Blue Zones", sweets are typically only served at festive occasions. Additional sugar is avoided as far as possible, and tea is usually sweetened with honey. On the other hand, one to two handfuls of nuts are consumed daily.
Bread is also part of the diet in three of the five "Blue Zones". It is prepared either with wholemeal flour or sourdough. It is rich in nutrients and has a lower glycemic index.
Almost all the foods consumed by centenarians in the "Blue Zones" grow within a radius of about 19 kilometres from their homes. In addition, people primarily consume "whole foods". In other words, these are foods that are not processed at all or only very slightly.
In some "Blue Zones," such as Sardinia and Okinawa, living and eating habits have changed in recent years. This has led to a decline in health and longevity in some communities. Nevertheless, the principles of the "Blue Zones" lifestyle are still applicable and relevant today.